The present disclosure relates to pH monitoring and, more particularly, to monitoring and controlling pH in drilling fluid.
Boreholes are drilled into earth formations for the exploration and production of hydrocarbons, subterranean fluids, and minerals. During drilling operations components in the drillstring are in contact with the drilling fluid. Drilling fluids can be water or oil based but sometimes gaseous drilling fluids are also used. Drilling fluid properties are tailored to optimize drilling operations. The pH-value of drilling fluids, for instance, is typically controlled to maintain certain levels of corrosion protection to the metallic materials in the drillstring.
Demanding service conditions characterized by high temperature and corrosive environments (e.g., environments containing high chloride concentrations and/or corrosive gasses (e.g., CO2, H2S, etc.)) can significantly reduce the reliability and service life of downhole equipment. Improper pH levels downhole contribute to corrosion such as pitting corrosion, environmentally assisted cracking (EAC), co-leaching, elastomers damage and secondary corrosion. It should be appreciated that pH-excursions from a desired pH range of 8 to 12 can be the leading cause of downhole equipment failures or the cause of significant damage to drilling equipment. This leads to costly non-productive time (NPT) and high repair costs.